I'm not a mod but I do know you need to give enough details for the bug to be reproduced by the developers so they have an easier time finding the cause of the issue. Although this might be a bug, I reckon it's more of a misunderstanding of how portals work on your side. You might want to look at the wiki to find why the portals aren't connected before assuming it's a bug.
STUDIOCRAFTapps
I'm not a mod but I do know you need to give enough details for the bug to be reproduced by the developers so they have an easier time finding the cause of the issue. Although this might be a bug, I reckon it's more of a misunderstanding of how portals work on your side. You might want to look at the wiki to find why the portals aren't connected before assuming it's a bug.